Olivetti series ET
Here there are some documents on the series of Olivetti ET (Electronic typewriter).
It encloses ET101, ET109, ET111 ET112, ET116, ET115, ET201, ET221, ET225, ET231, ET351.
It was a successfull series of electronic typewriters of 1980s, often with memory and a small display, and an interchangeable writing element, the "daisy".
More silent that a electric typewriter, more fast than a mechanical typewriter, it was the preferred in big offices. The cost was higher, so not every company found it convenient and those who had few volumes of writing preferred less expensive solutions.
It was a big jump from heavy and noisy typewriters, to electronic typewriters where you can change easily the font, had some memory, the touch was soft, and were easy to carry or move along the office.
Also he maintenance was easier. There weren't hundreds of parts moving, but only a few parts subjected to enough stress to break.
Here you can download some documents. Other will come.